Alexandre Raher

As Back-End Technical Lead at E.Leclerc, I manage the migration and evolution of SEM (Système d’Échange et Médiation), a critical application that aggregates and synchronizes millions of product data across e-commerce tools. I orchestrated the transition from a Node.js/MongoDB stack to a C#/.NET Core and PostgreSQL architecture, ensuring optimal performance (reducing query times from over 15 minutes to 15-30 seconds) and a clear, modular, and shared codebase with a focus on developer experience.

I design and implement robust back-end services (Hangfire jobs for batch processing, RESTful APIs), performant SQL queries, and handle Node.js/TypeScript micro-projects to meet specific needs. I place great importance on code quality (systematic reviews, SOLID best practices) and industrialization via CI/CD (GitLab), allowing me to quickly and safely deploy high-value business evolutions.

In this role, I design the architecture, approve code reviews, oversee automated deployments (GitLab CI/CD), and make strategic technical decisions for a small team. I work in Kanban, with dailies and weeklies, and excel at optimizing the processing of large data volumes (SQL, FTP/SFTP/Google Buckets integrations, Datadog & Kibana monitoring).

Passionate about the performance and industrialization of back-end solutions, I combine C#/.NET Core, Hangfire, and PostgreSQL expertise with a pragmatic DDD-oriented approach to ensure robustness and scalability in a 100% remote work environment.

Major contribution to the design and implementation of new features, and responsible for two major user experience enhancements. Optimization and refactoring of the Back-Office to improve user experience.

Migration of a large part of the functionalities from JavaScript to TypeScript and from React/Thunk to React-Query with drastic performance optimization.

Testing of all new and refactored components with React Testing Library and Cypress for critical page paths. Use of Storybook to facilitate component reusability and testing process. Implementation of best practices to improve the maintainability and optimization of the application as a whole.

Creation, development, and maintenance of the application's UI library.

Implementation of OpenAPI to facilitate the manipulation of different interfaces with TypeScript between Back-End and Front-End.

Maintenance and evolution on a Back Office specialized in fraud. Complete optimization and refactoring of the application with migration from JavaScript to TypeScript, from Redux-Saga to React-Query, implementation of Styled-Components for associated CSS with Javascript, structural reorganization of files, implementation of JavaScript unit tests and integration tests with React-Testing-Library.

Maintenance and evolution of the company's various Front-End libraries. Creation and enrichment of technical documentation related to Front-End within the company. Improvement of Developer Experience.

Participation in code reviews. Creation of POCs. UI design and performance optimization.

Training of new developers on Front-End and practices.